The present invention relates generally to the field of instrumentation, devices, and systems for treatment of the spine, and more particularly to methods and systems for interconnecting two or more portions of the spine and also devices for engaging an elongate member.
The spine is subject to various pathologies that compromise its load beating and support capabilities. Such pathologies of the spine include, for example, degenerative diseases, the effects of tumors and, of course, fractures and dislocations attributable to physical trauma. In the treatment of diseases, malformations or injuries affecting spinal motion segments (which include two or more adjacent vertebrae and the disc tissue or disc space therebetween), and especially those affecting disc tissue, it has long been known to remove some or all of a degenerated, ruptured or otherwise failing disc. It is also known that artificial discs, fusion implants, or other interbody devices can be placed into the disc space after disc material removal. External stabilization of spinal segments alone or in combination with interbody devices also provides advantages. Elongated rigid plates, rods and other external stabilization devices have been helpful in the stabilization and fixation of a spinal motion segment.
While the external stabilization systems of the prior art are a step in the right direction, there remains room for additional improvements. Oftentimes, the geometric and dimensional features of these systems and patient anatomy constrain the surgeon during surgery and prevent optimal placement, attachment and loading of the spinal motion segment.
Thus, there is a general need in the industry to provide methods and devices for stabilizing a spinal motion segment that reduce surgeon constraints during surgery and optimize placement and attachment of the stabilization devices to the spinal motion segment. There are also needed improved devices for connecting longitudinal members to the spinal column. There is also a need for stabilization devices that allow segmental motion to be maintained after attachment thereto. There are further needs for stabilization devices that maintain the desired corrective forces on the spinal motion segment. The present invention is directed to meeting these needs and others in a novel and unobvious manner.
The present invention provides a system with anchors interconnected by a flexible elongate member. Coupling members secure the elongate member to the anchors to maintain the corrective forces applied to the spinal motion segment by the elongate member.
The present invention further provides an anchor to which an elongate member can be attached. A coupling member can be coupled to the anchor to further secure the elongate member to the anchor.
The present invention also provides a cannulated anchor which receives a portion of a coupling member in the cannulation when the coupling member is coupled to the anchor. An elongate member can also be placed between the coupling member and the anchor, with the portion of the coupling member extending through the elongate member.
The present invention also provides an anchor having a penetrating element which at least partially penetrates an elongate member. A coupling member can be secured to the anchor. In one form, the penetrating element is received in the coupling member.
The present invention additionally provides a coupling member attachable to an anchor. The coupling member can be provided with any one of a number of variously configured elongate member engaging portions that penetrate and/or crimp an elongate member positioned between the coupling member and the anchor.
Methods for engaging an elongate member to a spinal motion segment are also provided. According to one method, first and second anchors are engaged to first and second vertebrae and compressed toward one another. An elongate member is engaged to the first and second anchors. According to another method, the elongate member is tensioned before it is attached to the anchors.
Further aspects, forms, objects, features, advantages and benefits of the present invention will become apparent from the drawings and description contained herein.